Method of locating salt or rock layers



JOHANN G. KOENIGSBERGIEIR, F FREIBURG, GERMANY' METHOJD 0F LOCATII\TG SAL1 OB ROCK LAYERS Alpp1icacion fild January 5, 1923, Serial N0. 610,898, and in Germany January 2, 1922.

My invention refers 130 a methocl of locat- 1ng the situation and form of salt deposits, gravel and rock layers and the like.

lt has been proposed by Mintrop to use 5 for this purpose long elastic waves ancl c0ncussions caused artificially by aid cf explosives, such waves being observed in a special instrument callecl seisrnograph and permittingto ascertain the nature 0f the subsoil.

011 the other band Fessenden has indicatecl a method for locat-ing ore bodies by inflectin 0f short acoustic waves, such inflection meaning refraction and reflection.

The present invention, being also based on the use 0f acoustic waves and elctroacoustic apparatus to record these waves, makes use of the modern sound-detecting apparatus, with 01 without amplifier tubes connected With oscillograph tubes 0r other recording clevices, or without such the novel object as regards the use of acoustic waves being the 10- cating of salt deposits, 0f the extension of the boundaries of layers of gravel and the like. Owing to the fach that the s0uhd-detecting devices are consiclerably cheaper and also more easily portable than seismographs for earthquake waves, ehe novel method permits of employing sound-detecting devices in various points at a time, and, therefore, to use a method differing from the one used with earthquake waves.

VVith or without conducting wires compar-ative observations can be macle, and if neces'sary, recorded a1: a Single point only. The

r time of the arrival of the waves, 0rof certain distinct marks in the trains of the waves may ben be compared with each 0ther and with the time at which the sound was produced, and also the intensity of ehe waves at the various points may be measured and compared.

In order to mrke my invention more clear,

I refer to ehe accompanying drawing in which are shovvn diagrammatically by way of example threedifierenbvertical Sections through portions of the seil and of the subseil.

Figure 1 represents a section of a deposit of gravel embedded in solid rock.

F igure 2 is a section of a salt deposit. Figure 3 illustrates a third modification.

Referring t0 Figure 1, 4 is the deposit of gravel, anal 5 is solid rock having the gravel embedded into it.

The source of sound is placed at the point l, and souncl detecting devices at the points 2 3 6 7. All these points 1 2 3 6 7 are connected electrically With a recording apparatus either by aid of a wire, or in the wireless way. Amplifiers may be inserted in these connections.

The sound ferent absolute tixnes.

The curve is received in the sound-detecting apparatus 2 3 6 Tand is elect-rically conducted 130 a recording device located at the point 8. The intensity curves thus electrically transmitted to the recording apparatus 8 are dir'ectly observed and measured, for instance, with the aid 0f a rotary mirror.

The relative (lisplacements of the times of said intensity curves may be compared by optical length measurements if the number of rotations of the mirror is known, 01' the electromagnetic eflect is recorded with the aid 0f a galvanometer.

Either way perrnits of drawing conclusions as to the length of the various ways, for instance from the point 1 over the points 2 and 3 to the point 6, and from the point 1 around the gravel 4 in the medium 5 to the point 6. The difierence of time which the sound requires to get from the point 2 to tl1e point 3 shows the velocity of the sound alongthe gravel 4. In the same manner the dilferences of time at the point-s 6 and 7 for the direct way across the gravel 4 shows the velocity Qf the sound along the medium 5. From the difl'erences of time for the two paths of sound which lead 130 the point 6, and with the aid cf the data previously obtained, the length of the unknown bounclary 1ine locat ed in the depth between 'the deposit of gravel 4 and the rock 5 may be determined.

A similar procedure is adapted in ascertaining the location of a layer 0:E salt (Figure The source of sound is placed at the point 1. Sound dete cting apparatus are placed at the points 2 and 3. Also in this case the difference in the t ime of arrival of the same proj-eotin of the inten'sity curve between the points l, 2 and3 is observed whereby the velociigy of travel of the sound through the soil 4 is obtained. Besides soundWaves are reflected at ehe boundary surface between the 1ayef of sa1t 5 and the soil 4, and these waves arrive at the poi nt 3 klter than the waves travelling directly fromthe point 1 to the point 3 and being propagat6d immediacely below the surface of th e soil. This permits of drawing conclusions regarding the length of the way and, conse quentlythe depth in Which fche salt deposit is to be found.

In .the third example (Figure3) the s0 urce of sound is placed at l; the sound-detectingapparatus at 2 311d. the recording apparatus at 8 At the point 2 there is received the wave propa 2ited directly below the surface of the soil; as we1l as the wave reflected by the deposit 5 and arriving at 2 correspondingly later. The diflerei1ce of tin 1e indicates the way of thereflected wave and, thus, th e dep'th in which the deposit commences,

1 yvhereas the speed of the souhd travelling through the soil 4= is determined by the difing at another point the direct acoustic w aves ference 0f time between the waves ascertaimad at the points 1 and 2;

- I wish it to be understood that I do not desire to be limitedto the exact details of procedure and Constructiofi herebefore described, 'as many obviousmodifications Will occur t0 a person skilled in the art.

I clai1rm l. The method of ascertaining the position and n'ature of a mineral deposit embedded in the seil comprising producing acoustic wave s at avpoint near said deposit varying at inter- Vals the intensity 0f such waves, receiving at another point the direcfi acoustic waves travelling frm said first point t0 said second point and also the acoustic waves reflected from said deposit and electrically recording both said kinds of waVes.

2. The method of ascertaining the osition and natura of a mineral deposit embedded in the seil comprising prgflucing acoustic wave at a point near said deposit varying at intervals the int'ensity of such waves, receivtravelling from said first point to said second point and also the acoustic Waves reflected from said deposit, convexting= said acoustic waves into electric oscillations and recording same.

3. The method of ascertaining the position and nature of a mineral deposit embedded in the soi1 comprising producing acoustic wave's at point near said deposit varyingatihterva1s the intensity of such waves, receiving at anothet point the direct acoustic waves traurelling from said first point to said second.

point and also the acoustic' waves reflected from saidde osit, converting said acoustic reflected from said deposit and electrically recordingbot-h said kinds of waves.

' In testimony whereof I affix my signature.

JOHANN G. KOENIGSBERGER. 

